Important Lessons Derived from X.500 Case Studies

X.500 is a new and complex electronic directory technology, whose basic specification was first published as an international standard in 1988, with an enhanced revision in 1993. The technology is still unproven in many organisations. This paper presents case studies of 15 pioneering pilot and operational X.500 based directory services. The paper provides valuable insights into how organisations are coming to understand this new technology, are using X.500 for both traditional and novel directory based services, and consequently are deriving benefits from it. Important lessons that have been learnt by these X.500 pioneers are presented here, so that future organisations can benefit from their experiences. Factors critical to the success of implementing X.500 in an organisation are derived from the studies

The Globe Infrastructure Directory Service

To implement adaptive replication strategies for Web documents, we have developed a wide area resource management system. This system allows servers to be managed on a local and global level. On a local level the system manages information about the resources and services provided by the servers, while on a global level the system allows servers to be searched for, added to, and removed from the system. As part of the system, and also in order to implement adaptive replication strategies, we introduce a hierarchical location representation for network elements such as servers, objects, and clients. This location representation allows us to easily and efficiently find and group network elements based on their location in a worldwide network. Our resource management system can be implemented using standard Internet technologies and has a broader range of applications besides making adaptive replication strategies possible for Web documents

Towards the definition of a quality model for mail servers

The paper presents an approach for building a Mail Server Quality Model, based on the ISO/IEC software quality standard. We start by defining the mail system domain to be used as general framework and the relevant technologies involved. Then a general overview of the ISO/IEC standard is given. The basic steps, the relevant considerations and criteria used to select the appropriated subcharacteristics and quality attributes are also presented. The selected attributes are categorized under the six ISO/IEC quality characteristics conforming the model. Finally some case studies requirements and two commercial mail server tools are used to evaluate the model.Postprint (published version

Leveraging simulation practice in industry through use of desktop grid middleware

This chapter focuses on the collaborative use of computing resources to support decision making in industry. Through the use of middleware for desktop grid computing, the idle CPU cycles available on existing computing resources can be harvested and used for speeding-up the execution of applications that have “non-trivial” processing requirements. This chapter focuses on the desktop grid middleware BOINC and Condor, and discusses the integration of commercial simulation software together with free-to-download grid middleware so as to offer competitive advantage to organizations that opt for this technology. It is expected that the low-intervention integration approach presented in this chapter (meaning no changes to source code required) will appeal to both simulation practitioners (as simulations can be executed faster, which in turn would mean that more replications and optimization is possible in the same amount of time) and the management (as it can potentially increase the return on investment on existing resources)

Security features using a distributed file system

Tese de mestrado em Segurnaça Informática, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2011Informação sensível como por exemplo dados provenientes the firewalls ou sistemas de detecção de intrusões, é preciso que seja armazenada durante longos períodos de tempo por razões legais ou para fins de análise forense. Com o crescimento das fontes geradores deste tipo de dados dentro de uma empresa, torna-se imperioso encontrar uma solução que cumpra os requisitos de escalabilidade, segurança, disponibilidade, performance e baixa manutenção com custos controlados. Na sequência desta necessidade, este projecto visa fazer uma análise sobre vários sistemas de ficheiros distribuídos por forma a encontrar uma solução que responda aos requisitos de performance e segurança de uma aplicação interna da Portugal Telecom. Para validar a solução, o projecto inclui a concepção de um protótipo que pretende simular as condições de execução dessa aplicação.Sensitive information such as firewall logs or data from intrusion detection systems, has to be stored for long periods of time for legal reasons or for later forensic analysis. With the growth of the sources generating this type of data within a company, it is imperative to find a solution that meets the requirements of scalability, security, availability, performance and low maintenance while keeping the costs under control. Following this need, this project aims to make an analysis of several distributed file systems in order to find a solution that meets both the performance and security requirements of an internal application of Portugal Telecom. To validate the solution, the project includes the design of a prototype that aims to simulate the execution environment of that application

Adaptive management of emerging battlefield network

The management of the battlefield network takes place in a Network Operations Center (NOC). The manager, based on the importance of the managed network, is sometimes required to be present all the time within the physical installations of the NOC. The decisions regard a wide spectrum of network configurations, fault detection and repair, and network performance improvement. Especially in the case of the battlefield network operations these decisions are sometimes so important that can be characterized as critical to the success of the whole military operation. Most of the times, the response time is so restricted that exceeds the mean physical human response limits. An automated response that also carries the characteristics of human intelligence is needed to overcome the restrictions the human nature of an administrator imposes. The research will establish the proper computer network management architecture for an adaptive network. This architecture will enhance the capabilities of network management and in terms of cost and efficiency.http://archive.org/details/adaptivemanageme109451678Lieutenant Commander, Hellenic NavyApproved for public release; distribution is unlimited